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Electrochemical CH4 oxidation is attractive as a strategy capable of conversion with high selectivity, but improving productivity remains a challenge. We demonstrate that CuO/CeO2 can serve as a ca...

Modern Pepper's ghost—“floating hologram”—systems generally use transparent screens called half mirrors or foils. this system must have the same screen size as the image size in order to display a large-sized image. Further, depth of the image can only be obtained from the distance between the screen and the display panel. These limitations can be overcome using holographic optical elements (HOE). HOE is made by recording as a refractive force of the lens with holographic material. In this study, the numerical values of the reconstructed images were theoretically analyzed through optical ray tracing, and the theoretical design of the reconstructed image size and depth plane was numerically measured and experimentally verified.

The dimple occurs by sudden pressure inversion at the droplet’s bottom interface when a droplet collides with the same liquid-phase or different solid-phase. The air film entrapped inside the dimple is a critical factor affecting the sequential dynamics after coalescence and causing defects like the pinhole. Meanwhile, in the coalescence dynamics of an electrified droplet, the droplet’s bottom interfaces change to a conical shape, and droplet contact the substrate directly without dimple formation. In this work, the mechanism for the dimple’s suppression (interfacial change to conical shape) was studied investigating the effect of electric pressure. The electric stress acting on a droplet interface shows the nonlinear electric pressure adding to the uniform droplet pressure. This electric stress locally deforms the droplet’s bottom interface to a conical shape and consequentially enables it to overcome the air pressure beneath the droplet. The electric pressure, calculated from numerical tracking for interface and electrostatic simulation, was at least 108 times bigger than the air pressure at the center of the coalescence. This work helps toward understanding the effect of electric stress on droplet coalescence and in the optimization of conditions in solution-based techniques like printing and coating.

Large porcelain tiles have attracted increased demand owing to their cost-effectiveness and superior esthetics. Here, an epoxy resin adhesive was injected into cement mortar, which was then applied to tiles. The adhesion performance of the tiles was subsequently evaluated in terms of the permeability and drying shrinkage under various curing conditions. The epoxy resin adhesive not only penetrated the tile&ndash, mortar and mortar&ndash, concrete interfaces, but also directly penetrated the mortar, thus enhancing the mechanical adhesion at each interface. In addition to the mechanical adhesion between the tiles and mortar, the epoxy resin adhesive prevents the degradation of adhesion due to shear stress by minimizing the moisture evaporation and shrinkage of the mortar. Evaluation of the adhesion characteristics under water and freeze&ndash, thaw curing conditions revealed the vulnerability of the epoxy resin to moisture, however, adequate adhesion performance was observed when the epoxy resin was air-cured prior to being exposed to harsh environments. Moreover, the injection method did not prolong the construction period, but could potentially reduce it during actual application. Nevertheless, further research on the adhesion performance of tiles with injected epoxy resin adhesive is required to evaluate the long-term durability.

Precise and rapid detection of biomolecules is a fast-growing research theme in the field of biomedical engineering. Based on the surface-enhanced Raman scattering, micro/nano-scale structures composed of noble metals (e.g., gold and silver) play a critical role in plasmonics. However, it is still limited to structuring nanomaterials in a specific manner. Here, we investigated a novel surface-enhanced Raman spectroscopy (SERS) application using one-dimensional nanomaterials and micro-encapsulation methods. With the immiscible nature of fluids, the nanomaterials were properly captured inside a number of droplets for encapsulation, deforming to micro-ring nanostructures. To yield uniform sizes of the silver micro-ring structures, a microchannel system was designed to characterize particle sizes via microscopic approaches. We were able to obtain printable silver nanowire micro-ring ink, and investigated the SERS substrate effect of the silver micro-ring structure. This fabrication method can be used in many other SERS-based biomedical engineering applications in the near future.

Leukocytes continuously circulate our body through the blood and lymphatic vessels. To survey invaders or abnormalities and defend our body against them, blood-circulating leukocytes migrate from the blood vessels into the interstitial tissue space (leukocyte extravasation) and exit the interstitial tissue space through draining lymphatic vessels (leukocyte intravasation). In the process of leukocyte trafficking, leukocytes recognize and respond to multiple biophysical and biochemical cues in these vascular microenvironments to determine adequate migration and adhesion pathways. As leukocyte trafficking is an essential part of the immune system and is involved in numerous immune diseases and related immunotherapies, researchers have attempted to identify the key biophysical and biochemical factors that might be responsible for leukocyte migration, adhesion, and trafficking. Although intravital live imaging of in vivo animal models has been remarkably advanced and utilized, bioengineered in vitro models that recapitulate complicated in vivo vascular structure and microenvironments are needed to better understand leukocyte trafficking since these in vitro models better allow for spatiotemporal analyses of leukocyte behaviors, decoupling of interdependent biological factors, better controlling of experimental parameters, reproducible experiments, and quantitative cellular analyses. This review discusses bioengineered in vitro model systems that are developed to study leukocyte interactions with complex microenvironments of blood and lymphatic vessels. This review focuses on the emerging concepts and methods in generating relevant biophysical and biochemical cues. Finally, the review concludes with expert perspectives on the future research directions for investigating leukocyte and vascular biology using the in vitro models.

In this study, we examined the effects of cement fineness, SO3 content, an accelerating agent, and chemical admixtures mixed with unit weights of cement on concrete early strength using concrete mixtures. C24 (characteristic value of concrete, 24 MPa) was used in the experiment conducted. Ordinary Portland cement (OPC), high fineness and SO3 OPC (HFS_OPC), and Early Portland cement (EPC) were selected as the study materials. The unit weights of cement were set to OPC 330, 350, and 380. Further, a concrete mixture was prepared with a triethanolamine (TEA)-based chemical admixture to HFS. A raw material analysis was conducted, and the compressive strength, temperature history, and maturity (D∙h) were examined. Then, the vertical formwork removal time was evaluated according to the criterion of each country. Finally, the time required to develop concrete strength of 5 MPa was estimated. Results showed that the early strength of concrete mixed with HFS and EPC was greater than that exhibited by concrete with an increased unit weight of cement with OPC. In addition, when HFS was used with EPC, its strength developed early, similar to the trend exhibited by EPC, even at low temperatures.

There have been many studies on the effect of durability and compressive strength on the increase of the mixing rate of admixtures. However, there is no research that can provide a guide on the optimal mixture proportions for maintaining compressive strength and secure durability properties when using local materials. Therefore, the purpose of this article is to assess the durability and engineering performances of concrete based on local fly ash (FA), as well as to derive the optimum CaO content scope for ensuring durability. The results of this study were compared with the results of the previous study of high-volume ground-granulated blast-furnace slag (GGBFS) concrete. To achieve this, tests were carried out by increasing the admixture mixing rate in 10% increments from 0% to 70%. The unit water was set at 175 kg/m3 and the amount of binder was set at 330 kg/m3. It was found that the overall compressive strength of the hardened concrete decreased when the admixture mixing rate increased. In addition, the compressive strength of specimens tended to improve as all the CaO contents of the admixture types increased. When the durability properties were examined, it was found that the relative dynamic elasticity modulus and carbonation depth decreased, and the chloride penetration depth increased as the CaO content increased for both GGBFS and FA. The weight loss rate, however, remained similar. Based on the results of this study, the optimal CaO content that achieved satisfactory engineering and durability properties was found to be between 39% and 48% for FA. The results of this study will be able to offer guidelines for the mixture rates of FA when mixing durable concrete for use in the field. Additionally, these results are expected to be utilized as a basis for determining instructions relating to chemical composition in order to develop binders with improved durability.

This paper presents a TCAD-to-SPICE high-sigma analysis of DRAM write and retention performance. Both statistical and process-induced variability are taken into- account. We highlight that the interplay between discrete traps and discrete dopants is ruling the leakage statistical tails and therefore can play a fundamental role in determining yield and reliability of ultra-scaled DRAMs.

This study proposes model formulae for predicting the strength of concrete by analyzing the relationships between the results of nondestructive testing (NDT) methods and the compressive strength of concrete specimens at the hardened stage. Further, NDT of concrete molds and mock-up specimens was conducted using NDT methods (rebound hammer, ultrasonic pulse velocity). The water/cement (W/C) ratios were set to 0.48, 0.41, and 0.33 to achieve concrete strengths within the compressive strength range of 24&ndash, 60 MPa. The evaluation parameters included the fresh concrete properties, compressive strength (mold and core), temperature history, maturity, rebound value, and ultrasonic pulse velocity. Evaluation results indicated that the reliability of existing models, based on the rebound and ultrasonic pulse velocity, is significantly low on high-strength concrete of 40 MPa or higher, and cannot satisfy the &plusmn, 20% error range. Consequently, this study proposes a regression equation of the concrete strength based on the experimental rebound and ultrasonic pulse velocity values in a 24&ndash, 60 MPa range, which offers satisfactory reliability.

Floating holograms using holographic optical element screens differ from existing systems because they can float 2D images in the air and provide a sense of depth. Until now, the verification of such displays has been conducted only on the system implementation, and only the diffraction efficiency and angle of view of the hologram have been verified. Although such displays can be directly observed with the human eye, the eye&rsquo, s control ability has not been quantitatively verified. In this study, we verified that the focus of the observer coincided with the appropriate depth value determined with experiments. This was achieved by measuring the amount of control reaction from the perspective of the observer on the image of the floating hologram using a holographic optical element (HOE). An autorefractor was used, and we confirmed that an image with a sense of depth can be observed from the interaction of the observer&rsquo, s focus and convergence on the 2D floating image using a HOE. Thus, the realization of content with a sense of depth of 2D projected images using a HOE in terms of human factors was quantitatively verified.

In the contemporary and future nanoelectronic devices, quantum effects play an important role in terms of confinement and tunneling. It is necessary to include a suitable implementation of such effects in advanced simulation tools. In this work, we report on a novel implementation of direct Source-to-Drain tunneling (S/D tunneling) which has been included in our 2D Multi-Subband Ensemble Monte Carlo (MS-EMC) simulator. The model has been validated against Non-Equilibrium Green's Function (NEGF) simulations. The effective mass variation in ultrathin channels has been calculated using density functional theory (DFT) and used in our MS-EMC simulations to study its impact on the device behavior. As a result, the quantum transport phenomena have been pragmatically implemented in MC tools.

The aim of this paper is to present a flexible and open-source multi-scale simulation software which has been developed by the Device Modelling Group at the University of Glasgow to study the charge transport in contemporary ultra-scaled Nano-CMOS devices. The name of this new simulation environment is Nano-electronic Simulation Software (NESS). Overall NESS is designed to be flexible, easy to use and extendable. Its main two modules are the structure generator and the numerical solvers module. The structure generator creates the geometry of the devices, defines the materials in each region of the simulation domain and includes eventually sources of statistical variability. The charge transport models and corresponding equations are implemented within the numerical solvers module and solved self-consistently with Poisson equation. Currently, NESS contains a drift–diffusion, Kubo–Greenwood, and non-equilibrium Green’s function (NEGF) solvers. The NEGF solver is the most important transport solver in the current version of NESS. Therefore, this paper is primarily focused on the description of the NEGF methodology and theory. It also provides comparison with the rest of the transport solvers implemented in NESS. The NEGF module in NESS can solve transport problems in the ballistic limit or including electron–phonon scattering. It also contains the Flietner model to compute the band-to-band tunneling current in heterostructures with a direct band gap. Both the structure generator and solvers are linked in NESS to supporting modules such as effective mass extractor and materials database. Simulation results are outputted in text or vtk format in order to be easily visualized and analyzed using 2D and 3D plots. The ultimate goal is for NESS to become open-source, flexible and easy to use TCAD simulation environment which can be used by researchers in both academia and industry and will facilitate collaborative software development.

This study aimed to evaluate the durability and engineering performance of concrete mixed with locally produced ground granulated blast-furnace slag (GGBS) based on CaO content and ratio, and to derive the optimal CaO content range that can secure durability. Hence, tests were conducted by increasing the GGBS replacement ratio by 10% from 0% to 70%, while the unit binder weight was fixed at 330 kg/m3. The results indicated that the compressive strength exhibited a tendency to increase when the CaO content and basicity increased within 28 d of age, although similar compressive strength characteristics were observed at 56 d of age, irrespective of the CaO content and basicity. Additionally, four test items (i.e., carbonation depth, chloride penetration depth, relative dynamic elastic modulus, and weight reducing ratio) were measured to evaluate durability. The optimal CaO content satisfying all four parameters was observed as ranging between 53% and 56% (GGBS replacement ratio: 27.5%&ndash, 47.1%). The results of the study can provide guidelines on the mixing proportions of GGBS concrete with excellent durability that can be applied to local construction sites and can be used as basic data to set chemical composition criteria for the development of binders to improve durability.

This study aims to analyze the engineering properties and durability of binary blended concrete incorporating pulverized coal combustion ash (PCC ash) produced in local areas and assesses the sustainability. For this, tests and evaluations were carried out under conditions in which the unit binder weight and unit water weight were fixed at 330 and 175 kg/m3, respectively, while the replacement ratio of PCC ash increased from 0% to 70% at 10% intervals. The results showed that the replacement ratio of PCC ash should be less than 38.9% in order to secure the target compressive strength (fck = 24 MPa) at the age of 28 days in field application. The durability test found that as the replacement ratio of PCC ash increased, the carbonation depth and relative dynamic elastic modulus increased, while the chloride penetration depth decreased. However, the weight&ndash, loss ratio remained similar. It was also found that the optimum PCC ash replacement ratio, which satisfies four durability parameters and can ensure the target compressive strength (fck = 24 MPa) in the case of mix proportion conditions set in this study, ranges from 20.0% to 38.9%. The sustainability assessment results showed that as the replacement ratio of PCC ash increased, the global warming potential (GWP), ozone layer depletion potential (ODP), acidification potential (AP), eutrophication potential (EP), photochemical ozone creation potential (POCP) and abiotic depletion potential (ADP) decreased. Therefore, it was proven that the replacement of PCC ash instead of ordinary Portland cement (OPC) under the same concrete mix proportions is effective at reducing environmental impacts.

The mixing proportions of concrete were examined with regard to the durability performance and early strength in coastal areas. Research was conducted to improve the C24 mix (characteristic strength of 24 MPa). C35 concrete (characteristic strength of 35 MPa) was selected as a comparison group, as it exhibits the minimum proposed strength criterion for concrete in the marine environment. To secure the early strength of the C24 concrete, 50% of the total ordinary Portland cement (OPC) binder was replaced with early Portland cement (EPC), and to provide durability, 20% was substituted with ground granulated blast-furnace slag (GGBS). In addition, a polycarboxylate (PC)-based superplasticizer was used to reduce the unit water content. The compressive strength, chloride ion diffusion coefficient, chloride penetration depth, and pore structure were evaluated. After one day, the compressive strength improved by 40% when using EPC and GGBS, and an average increase of 20% was observed over 91 days. EPC and GGBS also reduced the overall porosity, which may increase the watertightness of concrete. The salt resistance performance was improved because the rapid early development of strength increased the watertightness of the surface and immobilization of chloride ions, decreasing the chloride diffusion coefficient by 50%.

In this study, experiments were performed on the applicability of mortars and concretes based on calcium sulfoaluminate (CSA) binders to facilitate the early strength development of ordinary Portland cement (OPC) under low-temperature conditions. An optimum mixture of CSA was evaluated to improve the early strength of OPC, and the effects of accelerators and retarders on this mixture were examined to demonstrate the applicability of the resulting concrete mixture. Furthermore, mixture applicability was validated by producing concrete at the Remicon Batcher plant and performing numerical simulations. As observed, the optimum CSA substitution rate for the realization of early strength was 17% of the total unit binder amount with CaO/SO3 and SO3/Al2O3 ratios of 1.9 and 1.25, respectively. Evidently, CSA in combination with Na2SO4 as an accelerator promoted the early strength of concrete with OPC and secured its constructability using additional retarders to control the quick setting of concrete. Additionally, the activation of initial hydration at low temperatures yielded a compressive strength of 5 MPa/12 h or higher for the resulting concrete mixture.

As complementary metal-oxide-semiconductor (CMOS) transistors approach the nanometer scale, it has become mandatory to incorporate suitable quantum formalism into electron transport simulators. In this work, we present the quantum enhancement of a 2D Multi-Subband Ensemble Monte Carlo (MS-EMC) simulator, which includes a novel module for the direct Source-to-Drain tunneling (S/D tunneling), and its verification in the simulation of Double-Gate Silicon-On-Insulator (DGSOI) transistors and FinFETs. Compared to ballistic Non-Equilibrium Green’s Function (NEGF) simulations, our results show accurate I D vs. V GS and subthreshold characteristics for both devices. Besides, we investigate the impact of the effective masses extracted Density Functional Theory (DFT) simulations, showing that they are the key of not only the general thermionic emission behavior of simulated devices, but also the electron probability of experiencing tunneling phenomena., This project has received funding from EPSRC UKRI Innovation Fellowship scheme under grant agreement No. EP/S001131/1 (QSEE) and No. EP/P009972/1 (QUANTDEVMOD).

To investigate the effect of substitution position of the side group on a pyrene core, three derivatives having a triphenylbenzene group as a bulky side group at the 1,6-position, 4,9-position, and 1,8-position were successfully synthesized: 1,6-bis(5′-phenyl-[1,1':3′,1″-terphenyl]-4-yl)pyrene (1,6-DTBP), 4,9-bis(5′-phenyl-[1,1':3′,1″-terphenyl]-4-yl)pyrene (4,9-DTBP), and 1,8-bis(5′-phenyl-[1,1':3′,1″-terphenyl]-4-yl)pyrene (1,8-DTBP). The three synthesized materials showed excellent thermal stability with a high Tg of >140 °C and a high Td of >500 °C. Due to the highly twisted structure of 1,8-DTBP in the film state, the absolute photoluminescence quantum yield value was improved. Of the three synthesized materials used as an emitter in a non-doped organic light-emitting diode device, 1,8-DTBP showed highly efficient electroluminescence performance, with a luminance efficiency of 6.89 cd/A, power efficiency of 3.03 lm/W, and external quantum efficiency of 7.10% at 10 mA/cm2. In addition, 4,9-DTBP showed a deep-blue emission of CIE x, y (0.158, 0.063) suitable for HD-TV.

International audience; In this paper, we report a hierarchical simulation study on the electromigration problem in Cu-CNT composite interconnects. Our work is based on the investigation of the activation energy and self-heating temperature using a multiscale electro-thermal simulation framework. We first investigate the electrical and thermal properties of Cu-CNT composites including contact resistances using the Density Functional Theory and Reactive Force Field approaches, respectively. The corresponding results are employed in macroscopic electro-thermal simulations taking into account the self-heating phenomenon. Our simulations show that although Cu atoms have similar activation energies in both bulk Cu and Cu-CNT composites, Cu-CNT composite interconnects are more resistant to electromigration thanks to the large Lorenz number of the CNTs. Moreover, we found that a large and homogenous conductivity along the transport direction in interconnects is one of the most important design rules to minimize the electromigration.

Using an anthracene chromophore as a core group and a phenyl carbazole chromophore as a side group, three new emitters of blue light, 2-DCPA, 3-DCPA and 4-DCPA, were synthesized. The three compounds differed with regard to the position of the carbazole linked to the core, with 2-DCPA and 4-DCPA using carbazole nodes and 3-DCPA using the lobe position. Density functional theory calculations were performed to determine which positions of the carbazole moiety had node characteristics and which had lobe characteristics. The PLmax values of 2-DCPA, 3-DCPA and 4-DCPA in the film state were in the blue region, at 453, 457, and 452 nm, respectively. Of these materials, 3-DCPA, i.e., that with the linkage to the lobe position, showed the highest efficiency, with a value of 2.91 cd/A, and EQE, with a value of 2.65%. In a doped device using CBP as a host material and 3-DCPA as a dopant, the ELmax emission was observed to be in the deep blue region, at 433 nm, and with a CIE value of (0.150, 0.068).

The macroscopic assembly of two-dimensional materials into a laminar structure has received considerable attention because it improves both the mechanical and chemical properties of the original materials. However, conventional manufacturing methods have certain limitations in that they require a high temperature process, use toxic solvents, and are considerably time consuming. Here, we present a new system for the self-assembly of layer-by-layer (LBL) graphene oxide (GO) via an electrohydrodynamic (EHD) jet printing technique. During printing, the orientation of GO flakes can be controlled by the velocity distribution of liquid jet and electric field-induced alignment spontaneously. Closely-packed GO patterns with an ordered laminar structure can be rapidly realized using an interfacial assembly process on the substrates. The surface roughness and electrical conductivity of the LBL structure were significantly improved compared with conventional dispensing methods. We further applied this technique to fabricate a reduced graphene oxide (r-GO)-based supercapacitor and a three-dimensional (3D) metallic grid hybrid ammonia sensor. We present the EHD-assisted assembly of laminar r-GO structures as a new platform for preparing high-performance energy storage devices and sensors.

Organic-inorganic hybrid layer-by-layer (LBL) composite structures can not only increase the strength and ductility of materials but also well disperse nanomaterials for better-conducting pathways. Here, we discovered the self-assembly process of an organic and silver (Ag) LBL hybrid structure having excellent sustainability during the long-term bending cycle. During the assembly process, the organic and Ag hybrid structure can be self-assembled into a layered structure. Unlike other conventional LBL fabrication processes, we applied the hydrogel scaffold of a biological polymer, which can spontaneously phase separate into an LBL structure in a water/alcohol solvent system. This new hydrogel-based Ag LBL patterns can successfully be printed on a flexible polyimide film without nozzle-clogging problem. Although these Ag LBL patterns cracked during the bending cycle, carbonized organic compounds between the Ag layers help to self-heal within few minutes at a low temperature (

The characteristic performance of n-type and p-type inversion (IM) mode, accumulation (AC) mode and junctionless (JL) mode, bulk Germanium FinFET device with 3-nm gate length (LG) are demonstrated by using 3-D quantum transport device simulation. The simulated bulk Ge FinFET device exhibits favorable short channel characteristics, including drain-induced barrier lowering (DIBL

We investigate the performance of hysteresis-free short-channel negative-capacitance FETs (NCFETs) by combining quantum-mechanical calculations with the Landau-Khalatnikov equation. When the subthreshold swing (SS) becomes smaller than 60 mV/dec, a negative value of drain-induced barrier lowering is obtained. This behavior, drain-induced barrier rising (DIBR), causes negative differential resistance in the output characteristics of the NCFETs. We also examine the performance of an inverter composed of hysteresis-free NCFETs to assess the effects of DIBR at the circuit level. Contrary to our expectation, although hysteresis-free NCFETs are used, hysteresis behavior is observed in the transfer properties of the inverter. Furthermore, it is expected that the NCFET inverter with hysteresis behavior can be used as a Schmitt trigger inverter.

Selective modification and regional alterations of the surface property have gained a great deal of attention to many engineers. In this paper, we present a simple, a cost-effective, and amendable reforming method for disparate patterns of hydrophilic regions on super-hydrophobic surfaces. Uniform super-hydrophobic layer (Contact angle; CA > 150°, root mean square (RMS) roughness ∼0.28 nm) can be formed using the atmospheric radio frequency (RF) plasma on top of the selective hydrophilic (CA ∼ 70°, RMS roughness ∼0.34 nm) patterns imprinted by electrohydrodynamic (EHD) jet printing technology with polar alcohols (butyl carbitol or ethanol). The wettability of the modified surface was investigated qualitatively utilizing scanning electron microscopy (SEM), atomic force microscopy (AFM), and wavelength scanning interferometer (WSI). Secondary ion mass spectroscopy (SIMS) analysis showed that the alcohol addiction reaction changed the types of radicals on the super-hydrophobic surface. The wettability was found to depend sensitively on chemical radicals on the surface, not on surface morphology (particle size and surface roughness). Furthermore, three different kinds of representative hydrophilic samples (polystyrene nano-particle aqueous solution, Salmonella bacteria medium, and poly(3,4-ethylenediocythiophene) ink) were tested for uniform deposition onto the desired hydrophilic regions. This simple strategy would have broad applications in various research fields that require selective deposition of target materials.

Hetero dual-core derivatives that combine anthracene and pyrene were systematically studied for the purpose of producing highly efficient blue light-emitting materials applicable to organic light-emitting diode (OLED) lighting. Five compounds were designed in order to (1) determine which one of the two core chromophores in a hetero dual-core moiety, if any, acts as the main contributor to the optical and electronic properties of the final compounds, (2) control the electron-donating ability of the side group, and (3) change the substitution position. 1-[1,1′;3′,1′′]terphenyl-5′-yl-6-(10-[1,1′;3′,1′′]terphenyl-5′-yl-anthracen-9-yl)-pyrene (TP-AP-TP) was used as the reference material, and four other materials, including diphenyl-[10-(6-[1,1′;3′,1′′]terphenyl-5′-yl-pyren-1-yl)-anthracen-9-yl]-amine (DPA-AP-TP), diphenyl-[6-(10-[1,1′;3′,1′′]terphenyl-5′-yl-anthracen-9-yl)-pyren-1-yl]-amine (TP-AP-DPA), diphenyl-{4-[10-(6-[1,1′;3′,1′′]-terphenyl-5′-yl-pyren-1-yl)-anthracen-9-yl]-phenyl}-amine (TPA-AP-TP) and diphenyl-{4-[6-(10-[1,1′;3′,1′′]terphenyl-5′-yl-anthracen-9-yl)-pyren-1-yl]-phenyl}-amine (TP-AP-TPA), were synthesized as model compounds. The synthesized materials showed absorption wavelength peaks at 403–410 nm in the film state and exhibited PL emissions of 458–505 nm. Also, anthracene was shown to be the main core contributing to the optical and electronic properties. Among the synthesized molecules, the TPA-AP-TP molecule, in which triphenylamine, with its optimum electron-donating ability, was substituted into anthracene, showed excellent electroluminescence (EL) performance for OLED lighting with a current efficiency of 8.05 cd A−1, external quantum efficiency of 6.75%, and narrow EL FWHM of 53 nm.

Using a 1-anthracen-9-yl-pyrene (AP) dual-core emitter, two new emitters of blue light, 1-spiro-9,9′-bifluoren-4-yl-6-(10-spiro-9,9′-bifluoren-4-yl-anthracen-9-yl)-pyrene (DSF-AP) and 1-[2-(9H-carbazol-9-yl)phenyl]-6-[2-(9H-carbazol-9-yl)phenyl-anthracen-9-yl]-pyrene (DCP-AP), were synthesized through boration and the Suzuki aryl-aryl coupling reaction. These two materials exhibited PLmax values at 443 nm and 448 nm in a chloroform solution, and at 458 nm and 463 nm in a thin-film state. EL devices with the synthesized compounds were fabricated in the following configuration: ITO/4,4′,4″-tris(N-(2-naphthyl)-N-phenylamino)triphenylamine (2-TNATA) (60 nm)/N,N′-bis (naphthalene-1-yl)-N,N′-bis(phenyl)benzidine (NPB) (15 nm)/synthesized blue light-emitting materials (35 nm)/Tris-(8-hydroxyquinoline)aluminum (Alq3) (20 nm)/lithium fluoride (LiF) (1 nm)/Al (200 nm). Compared with the device made using an AP core lacking side groups, the device made with DCP-AP displayed 31% higher luminance efficiency (resulting in a value of 4.37 cd/A) and 32% higher power efficiency (to yield 1.93 lm/W), as well as a high external quantum efficiency (3.64%).

In the simulation-based research of aggressively scaled CMOS transistors, it is mandatory to combine advanced transport simulators and quantum confinement effects with first-principle techniques, which are the state-of-the-art to calculate the electronic band structure of nanomaterials. In this work, we have calculated the effective masses in DGSOI transistors and FinFETs using density functional theory (DFT) and investigate their impact on direct Source-to-Drain tunneling (S/D tunneling) using a 2D Multi-Sub-band Ensemble Monte Carlo (MS-EMC) simulator. The results for a particular V DS = 0.5 V show that, in the subthreshold regime, the effective mass variation increases the tunneling probability for the DGSOI transistor leading to a current degradation, whereas this difference is reduced and even reversed for the FinFET.

In this paper we present state of the art coupled-mode space based Non-Equilibrium Green Function approach for modeling quantum transport accurately in the vertically stacked Silicon nanowire (SiNW) FETs. Random discrete dopants (RDD) and metal grain granularity (MGG) induced variability in stacked SiNW FETs are also investigated. Furthermore, charge spectrum, current spectrum w.r.t. sub bands and the space-resolved Local Density of States (LDOS) corresponding to the location of band edge are analyzed in detail. The newly developed flexible and computationally efficient models implemented in quantum transport simulation tool NESS provides valuable insights on the effect of RDD and MGG variability on Sub-Threshold Swing (SS), Threshold Voltage $( \mathrm {V}_{TH})$ shift, On/Off Current $( \mathrm {I}_{ON}/ \mathrm {I}_{OFF})$ ratio and quantum confined charge transport mechanism.

Solid-state microsupercapacitors with ultrahigh areal-number-density are integrated on a chip via high-fidelity printing., Microsupercapacitors (MSCs) have garnered considerable attention as a promising power source for microelectronics and miniaturized portable/wearable devices. However, their practical application has been hindered by the manufacturing complexity and dimensional limits. Here, we develop a new class of ultrahigh areal number density solid-state MSCs (UHD SS–MSCs) on a chip via electrohydrodynamic (EHD) jet printing. This is, to the best of our knowledge, the first study to exploit EHD jet printing in the MSCs. The activated carbon-based electrode inks are EHD jet-printed, creating interdigitated electrodes with fine feature sizes. Subsequently, a drying-free, ultraviolet-cured solid-state gel electrolyte is introduced to ensure electrochemical isolation between the SS–MSCs, enabling dense SS–MSC integration with on-demand (in-series/in-parallel) cell connection on a chip. The resulting on-chip UHD SS–MSCs exhibit exceptional areal number density [36 unit cells integrated on a chip (area = 8.0 mm × 8.2 mm), 54.9 cells cm−2] and areal operating voltage (65.9 V cm−2).

With the advancement of media and computing technologies, video compositing techniques have improved to a great extent. These techniques have been used not only in the entertainment industry but also in advertisement and new media. Match-moving is a cinematic technology in virtual-real image synthesis that allows the insertion of computer graphics (virtual objects) into real world scenes. To make a realistic virtual-real image synthesis, it is important to obtain internal parameters (such as focal length) and external parameters (position and rotation) from an Red-Green-Blue(RGB) camera. Conventional methods recover these parameters by extracting feature points from recorded video frames to guide the virtual camera. These methods fail when there is occlusion or motion blur in the recorded scene. In this paper, we propose a novel method (system) for pre-visualization and virtual-real image synthesis that overcomes the limitations of conventional methods. This system uses the spatial understanding principle of Microsoft HoloLens to perform the match-moving of virtual-real video scenes. Experimental results demonstrate that our system is much more accurate and efficient than existing systems for video compositing.

We perform fast comb spectroscopy by dividing the probe comb into several sub-comb segments so as to produce multi-heterodyne beats focused around targeted molecular absorption lines. This concentrated scheme of comb spectroscopy is able to achieve a 30 dB signal-to-noise ratio with just a single shot measurement of 10 μs acquisition time. Such high signal sensitivity is verified by measuring separate absorption lines of H13C14N and 12CO2 gases simultaneously. In addition, atmospheric 12CO2 concentration over a 1.3 km open-air path is traced with a signal repeatability of 15 ppm at a 5 kHz update rate. Published version

In this work, we present a systematic simulation study of numerous copper (Cu) grain boundaries with the nonequilibrium Green's function (NEGF) framework based on the Density Functional Theory (DFT). In order to evaluate the effect of specific resistivity of various grain boundary profiles we developed the required methodology and we proposed an analytical equation for predicting the specific resistivity at each GB configuration. Moreover, in this work we also considered different crystal transport orientations and coincidence site lattices. Based on our simulations, we found that the specific grain boundary resistivity strongly depends on the transport orientations of the grains but not on the coincidence site lattice (CSL) density.

The dynamic tuning of ion concentrations has attracted significant attention for creating versatile functionalities of materials, which are impossible to reach using classical control knobs. Despite these merits, the following fundamental questions remain: how do ions affect the electronic bandstructure, and how do ions simultaneously change the electrical and magnetic properties? Here, by annealing platinum-dotted La0.67 Sr0.33 MnO3 films in hydrogen and argon at a lower temperature of 200 °C for several minutes, a reversible change in resistivity is achieved by three orders of magnitude with tailored ferromagnetic magnetization. The transition occurs through the tuning of the double exchange interaction, ascribed to an electron-doping-induced and/or a lattice-expansion-induced modulation, along with an increase in the hydrogen concentration. High reproducibility, long-term stability, and multilevel linearity are appealing for ionic-electric-magnetic coupled applications.

In this study, we investigated the wetting transition of a moving meniscus in a grooved microchannel through a detailed parametric study based on measurement by an optical tool and μ-particle image velocimetry (PIV) to avoid the transition in designing the microchannel. The parameters investigated were pitch, flow rate, and height of a microchannel. The contact angle, contact speed, and interfacial pressure difference were analyzed according to the parameters. We found that the pitch is most effective, the flow rate is moderately effective, and the height is least effective on that. The height even does not affect the contact angle, because the solid–fluid interaction at the groove edge is stronger than the fluid–air interaction. As the critical correlation, the contact angle, which is dependent on the pitch and the flow rate, and the height affect the air pressure between the grooves, which governs the air penetration flux and mainly determines the wetting transition. Therefore, a powerful way to delay the wetting transition is to reduce the degree of air pressure variation, specifically with a low pitch and a tall height with a low flow rate. Eventually, understanding dominant input parameters in relation to the wetting transition will be very useful in the design stage of microfluidic applications.

Chrysene, which has a wide band gap, was selected as an emission core to develop and study new materials that emit ultra-deep-blue light with high efficiency. Six compounds introducing various side groups were designed and synthesized: 6,12-bis(3′,5′-diphenylphenyl)chrysene (TP-C-TP), 6-(3′,5′-diphenylphenyl)-12-(3\,5\-diphenylbiphenyl-4′′-yl)chrysene (TP-C-TPB) and 6,12-bis(3′′,5′′-diphenylbiphenyl-4′-yl)chrysene (TPB-C-TPB), which contained bulky aromatic side groups; and N,N,N′,N′-tetraphenyl-chrysene-6,12-diamine (DPA-C-DPA), [12-(4-diphenylamino-phenyl)-chrysen-6-yl]-diphenylamine (DPA-C-TPA) and 6,12-bis[4-(diphenylamino)phenyl]chrysene (TPA-C-TPA), which contained aromatic amine groups, were designed to afford improved hole injection properties. The synthesized materials showed maximum absorption wavelengths at 342–402 nm in the film state and exhibited deep-blue photoluminescence (PL) emissions at 417–464 nm. The use of TP-C-TPB in a non-doped organic light-emitting diode (OLED) device resulted in ultra-deep-blue emission with an external quantum efficiency (EQE) of 4.02% and Commission Internationale de L'Eclairage coordinates (CIE x, y) of (0.154, 0.042) through effective control of the internal conjugation length and suppression of the π–π* stacking. The use of TPA-C-TPA, which includes an aromatic amine side group, afforded an excellent EQE of 4.83% and excellent color coordinates CIE x, y of (0.147, 0.077).

The uniform dispersion of Si materials in a carbon matrix while maintaining the nanomorphology of Si is required to achieve higher performance lithium-ion batteries (LIBs). Carbon-coated silicon nanoparticles embedded in monodisperse carbon spheres (C-SNP/CSs) were assembled by a simple mixing approach. We obtained high silicon contents up to 56 wt% for the composite electrodes. The C-SNP/CS anodes delivered a reversible specific capacity of 1230 mA h g−1 for 56 wt% Si and 953 mA h g−1 for 44 wt% Si at 800 mA g−1 after 150 charge/discharge cycles. The capacity retention after 150 cycles was 73% for the 56 wt% Si and 86% for 44 wt% Si C-SNP/CS electrodes, while the bare C-SNPs without CSs displayed only 32% retention. The high cycle performance indicates that the CSs effectively alleviated the mechanical stress induced by the large volume changes of Si during the charge/discharge cycles. Moreover, the high capacity retention reveals the high electrical conductivity of the electrodes, provided by the assembled morphology the CSs and the carbon-shell on the silicon nanoparticles(SNPs). The use of CSs with C-SNPs is a facile method to obtain a uniformly-dispersed mixture and can be readily scaled for practical applications.

Organic light-emitting diodes (OLEDs) have been successfully commercialized in the mobile phone market, and considerable effort is currently being devoted to applying OLEDs in other commercial applications such as televisions (TVs) and lighting. OLED displays are becoming the mainstream of next-generation displays to replace the liquid crystal display (LCD). Many technological advances are needed to apply OLEDs in TVs and lighting, but the development of fluorescent materials that emit short-wavelength blue light is especially essential for the future use of OLED displays. Usable fluorescent blue light-emitting materials must not only emit a deep blue light but also be thermally stable, highly efficient and have a long lifetime. There has been recent progress in research on blue fluorescent materials, and a resulting plethora of information. These results require a systematic organization to decipher the relationships between chemical structure and OLED device performance. We aim to address this need in the current review by systematically classifying blue fluorescent materials from a conceptually new “core-side” perspective, summarizing features that increase efficiency to improve OLED device performance, and providing a practical guideline for studying new blue fluorescent materials. This article summarizes the chemical structures and efficiency characteristics of selected 126 blue fluorescent materials. Systematic studies based on chemical structure and increased efficiency effects are necessary to develop highly efficient deep-blue fluorescent materials, and such studies on blue fluorescent materials are expected to become more prevalent in the fields of TV and lighting, as well as future flexible displays. Also, a systematic classification and understanding of the materials that have already been reported will aid the development and study of new light-emitting materials through quantitative and qualitative approaches.

This study analyzed the performance evaluation of alkali-activated composites (AAC) with an alkali-sulfate activator and determined the expected effects of applying AACs to actual sites. Results revealed that when the binder weight was increased by 100 kg/m3 at 7 days of age, the homogel strength of ordinary Portland cement (OPC) and AAC increased by 0.9 and 5.0 MPa, respectively. According to the analysis of the matrix microstructures at 7 days of age, calcium silicate hydrates (C&ndash, S&ndash, H, Ca1.5SiO3.5&middot, H2O) and ettringite (Ca6Al2(SO4)3(OH)12&middot, 26H2O) were formed in AAC, which are similar hydration products as found in OPC. Furthermore, the acid resistance analysis showed that the mass change of AAC in HCl and H2SO4 solutions ranged from 36.1% to 88.0%, lower than that of OPC, indicating AAC&rsquo, s superior acid resistance. Moreover, the OPC and AAC binder weight ranges satisfying the target geltime (20&ndash, 50 s) were estimated as 180.1&ndash, 471.1 kg/m3 and 261.2&ndash, 469.9 kg/m3, respectively, and the global warming potential (GWP) according to binder weight range was 102.3&ndash, 257.3 kg CO2 eq/m3 and 72.9&ndash, 126.0 kg CO2 eq/m3. Therefore, by applying AAC to actual sites, GWP is expected to be 29.5 (28.8%)&ndash, 131.3 (51.0%) kg CO2 eq/m3 less than that of OPC.

We present a facile method based on the coffee ring effect that can rapidly detect antibiotic-resistant bacteria, as an affordable genetic testing platform. When a colloidal solution of particles is dropped onto a substrate surface, an outward capillary flow upon evaporation induces the migration of the particles to the periphery of the droplet, forming a characteristic ring pattern. Herein, we utilize capture DNA microbeads which in the presence of target nucleic acid, form suppressed ring patterns by hybridization-induced crosslinking of the microbeads. The coffee ring-based assay is integrated with isothermal amplification based on rolling circle amplification (RCA), to produce long, single-stranded target DNA and induce hybridization, via a one-step procedure (i-CoRi assay). The resultant ring patterns can be simply observed with the naked eye or recorded with a standard mobile device for readout. The i-CoRi assay was validated for the rapid and specific detection of the antibiotic resistance gene mecA for MRSA, showing that detection was possible at the sub-zeptomolar range (~0.2 zM) with the specificity of distinguishing 2 mismatched bases. The spatial patterns of the microbeads were characterized, showing the dense packing of the microbeads at the center of the droplet and thinning of the ring pattern for the MRSA target, which were distinct from the negative controls MSSA, E. coli, and P. aeruginosa. The images of the microbead patterns were also processed by a simple readout algorithm to discriminate the presence or absence of the coffee ring, to enable diagnostic decision making. The current method provides a rapid and versatile platform for the specific identification of bacterial pathogens and multidrug resistance, especially for diagnosis in resource-limited settings.

This study examines effects of cement fineness and chemical admixtures of early strength agents on the early strength development of concrete. Three cement types were selected, namely ASTM type-I ordinary Portland cement (OPC), fineness ordinary Portland cement (FOPC), and ASTM type-III early Portland cement (EPC), and the mixing proportions of concrete were set by adding a triethanolamine-based chemical admixture to FOPC. The evaluation items considered in this study included raw material analysis, compressive strength, and maturity (D∙h). The time required for the development of concrete strength of 5 MPa in the three cement types was estimated and compared. The results revealed that using FOPC enhances the strength development of concrete owing to its higher fineness and SO3 content compared to OPC. In addition, it has been observed that using both FOPC and TCA yields a similar performance to that observed using EPC, in light of the improved early strength development at low temperatures.

The formation of an immunological synapse (IS) on recognition of a cancer cell is the main mechanism underlying the natural killer (NK)-cell-mediated killing of tumor cells. Herein, an integrative strategy for cancer therapy against solid tumors is reported, in which alterations in the cleft of IS, following the secretion of acidic granular content, are utilized as a trigger for the delivery of chemotherapeutic drugs. NK cells are decorated with the IS-environment-responsive micellar system to ensure the release of the payload when they attack cancer cells. Using this strategy, the immunological cytotoxic killing effect of NK cells against solid tumors is reinforced with the site-specific diffusion of chemotherapeutic agents. Harnessing the intrinsic mechanism for the recognition of abnormal cells and the tumor-homing effect of NK cells limit the adverse systemic effects of chemotherapeutic drugs. This approach may provide a pragmatic platform for the universal and effective utilization of IS formation.

International audience; In this paper, the impact of charge transfer doping on the variability of multiwalled carbon nanotube (MWCNT) local interconnects is studied by experiments and simulations. We calculate the number of conducting channels of both metallic and semiconducting carbon nanotubes as a function of Fermi level shift due to doping based on the calculation of transmission coefficients. By using the MWCNT compact model proposed in Part I of this paper, we study the charge transfer doping of MWCNTs employing Fermi level shift to reduce the performance variability due to changes in diameter, chirality, defects, and contact resistance. Simulation results show that charge transfer doping can significantly improve MWCNT interconnect performance and variability by increasing the number of conducting channels of shells and degenerating semiconducting shells to metallic shells. As a case study on an MWCNT of 11 nm outer diameter, when the Fermi level shifts to 0.1 eV, up to ~80% of performance and standard deviation improvements are observed. Furthermore, a good match between experimental data and simulation results is observed, demonstrating the effectiveness of doping, the validity of the MWCNT compact model and proposed simulation methodology.

International audience; In this paper, an enhanced compact model of multiwalled carbon nanotube (MWCNT) interconnects while considering defects and contact resistance is proposed. Based on the atomistic-level simulations, we have found that defect densities impact MWCNT resistance and ultimately their electrical performance. Furthermore, we have computed by atomistic-level simulations, the end-contact resistance between single-wall carbon nanotube and palladium (Pd) electrode to mimic the Pd-CNT end-contact resistance of each CNT shell in MWCNT. We have developed an advanced shell-by-shell model to include various parameters, such as shell diameter, shell chirality, defects on each shell, and connectivity of each shell to end contacts. We run Monte Carlo simulations to perform variability studies on each of these parameters to understand the electrical performance variation on MWCNT interconnects. We present the simulation results to convey the critical impact of variations. The impact of doping on MWCNT variability in the form of Fermi level shift will be addressed in Part II of this paper.

In this work, we introduce a novel procedure to compute the direct band-to-band tunneling in semiconductor nano-devices by combining the effective mass approximation, the non-equilibrium Greens function technique, and the two-band Flietner model of the imaginary dispersion. The model is first tested on a Si-InAs nanowire p-type tunnel field-effect transistor (p-TFET), showing great accuracy at much less computational cost when compared with atomistic simulations. Secondly, we report a preliminary quantum transport simulation study of the impact of random discrete dopants on Si-InAs nanowire p-TFETs. An ensemble of 63 InAs-Si nanowire TFETs has been simulated, revealing a strong dopant-induced variability.

In this letter, we report a quantum transport simu- lation study of the impact of Random Discrete Dopants (RDD)s on Si-InAs nanowire p-type Tunnel FETs. The band-to-band tunneling is simulated using the non-equilibrium Green’s func- tion formalism in effective mass approximation, implementing a two-band model of the imaginary dispersion. We have found that RDDs induce strong variability not only in the OFF-state but also in the ON-state current of the TFETs. Contrary to the nearly normal distribution of the RDD induced ON-current variations in conventional CMOS transistors, the TFET’s ON- currents variations are described by a logarithmic distribution. The distributions of other Figures of Merit (FoM) such as threshold voltage and subthreshold swing are also reported. The variability in the FoM is analysed by studying the correlation between the number and the position of the dopants.

In this study, the influences of chemical composition and fineness on the development of concrete strength by curing conditions were investigated through performance evaluation of high SO3 Portland cement (HSPC) and ordinary Portland cement (OPC). At the same fineness (3800 cm2/g), the initial and final setting times of HSPC were 92 and 98 min less than OPC. Early mortar compressive strength was approximately 176% higher after 24 h. After curing for 15 h, 18 h, and 24 h, the maturity of HSPC concrete (107.4%, 109.6%, and 111.7%) and early compressive strength (146.4%, 170.7%, and 154.5%) were higher than measured for OPC concrete. HSPC fineness was 111.8% higher than OPC, leading to early activation of the hydration reaction. By X-ray fluorescence analysis, the SO3 content of HSPC was 107.9% that of OPC. The applicable time for HSPC concrete form removal was shorter than that for OPC concrete. The relationships y = &minus, 10.57 ln(x) + 47.30 and y = &minus, 9.84 ln(x) + 44.05 were estimated for predicting the early-age strength OPC and HSPC concrete. Therefore, applying HSPC concrete to an actual construction site is expected to shorten the construction period and reduce the heating curing cost in winter compared to OPC concrete.